How could a warm breeze create a concreted baseball-sized spot on a wall?
You know what, that actually may be a brilliant answer, the refrigerant would have to be somewhere in this area to get to the furnace. And the system had just been running. Thanks for that suggestion.
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Nope.
Only if running a heat pump in heat mode.
Will not show up from the exterior wall though. Too much insulation and wind movement to concentrate that exception.
Could also be hot water pipe, especially if it is on a circulation circuit.
Not directly, but wind does cause changes in building pressure. If the building goes negative, it will suck air into the wall and will cause this.
From what I see, this looks like improperly installed insulation. I also saw something off to the side of one of your scans that looks like an insulation issue, maybe.
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I can’t be so quick to say that it wouldn’t show up at an exterior wall due to insulation and air movement. As a HERS Rater I see alot of poorly installed insulation as well as poorly installed refrigerant lines that have damaged insulation and are protruding past the face of the studs and will inevitably be in direct contact with the drywall.
You can trust me, I’m a Lvl III Thermographer and an HVAC System Design Engineer. Like you, I also did BPI training in the past. BPI actually stole some of my IR Scans and presented them to me during the course! 
The only way you will get the heat to see through the wall is a heat pump in the heat mode.
The suction line has all the heat to heat the house. It is also required to be insulated up to the indoor coil.
In the cooling mode, an A/C or Heat pump the liquid line should not exceed much more than the outdoor air (or the unit is in dire need of cleaning).
So regardless of the wall R-Value, there is not enough heat to conduct through the mass of the wall, insulated or not.
Interior of the wall, yes you can see it.
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I think Joshua is talking about the suction line run inside the exterior wall. The suction lines(during cooling) that run through the exterior wall almost always show up on thermal on new construction. Your typical exterior wall is 2x4. The suction line, liquid line, and thermostat wiring as a bundle takes up about 60% of that 3.5 inch thick wall. There is only a little space left to shove in some batt insulation around the bundle, hence why it so easily shows up on thermal.
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I see this thread is on-going with some very good comments. If you wish to pursue this level of infrared interpretation, my recommendation is that you take a quality series of building science courses. Consider pursuing certification as a Building Analyst Technician through the Building Performance Institute. I took my training through Green Training. Their courses apply for NACHI CE credits.
NACHI has a series of CE courses on Building Science. I did find this one course but I believe there is a whole series offered, which is what you may want to pursue. I don’t know how they compare to the Green Training courses.
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The reason I mentioned further training is that besides the potential issues noted above, you should consider that there may be a convection loop present inside that wall system. Your IR images suggest this is a possibility to consider, in addition to your noted warm spot and the void on the LH side of one of your images:
I’ve witnessed convection loops to be present in several homes in the ceiling, to the point that condensation resulted in significant bulk water leakage into the home proper. It’s a real issue.
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David, I believe we are in agreement that the heat pump system must be in heat mode and the suction line would be the heat source. I don’t disagree with your statement, I just think that you may have misunderstood what my logic was. When I was referring to the refrigerant lines being poorly installed I meant that they may not have been properly bent and secured to the stud, possibly allowing them to be in direct contact with drywall in one or more areas. The direct contact would most likely allow enough heat to transfer from the suction line to show up on the thermal camera, especially if the insulation on the suction line was damaged. I only say this because my background includes managing an HVAC company and I have seen my share of people trying to get away with sloppy work, lol.
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I assumed “other side of the wall”, not inside. This is an exterior wall, not a partition wall. Can tell by the thermal pattern. The studs are cooler because they are more conductive than the insulation.
You are aware of the R-Vale of the Armor flex insulation that must be installed on the suction line in all cases, and be airtight, or you will be looking at a flood inside the wall? Even if toughing the sheetrock, you will not see it with most cameras out there.
You do not get convection or conduction heat transfer that can be seen inside a wall if installed.
The reason for that is improper insulation installation.
When they stuff pipes in with the insulation, they leave convection air spaces and reduce the R-Value of the insulation and the entire wall R-Value. See it all the time. It shows up because of the air pocket, not heat transfer. You’re finding the line set, but not the cause of the anomaly. Doesn’t really matter, so long as you find what you’re looking for. 
See Michael Senty’s post above. It may be a loop like he shows, but is generally a one way air flow from one pipe hole penetration to the other (top plate/bottom plate).
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That was just an example of “anything.” Your temperature range was 50.5 to 62 F in your first image, a total of 11.5 degrees. The range in the second was 49.2 to 57.6 F, a total of 8.4 degrees. Interpreting from those thermal images, that portion of the wall has an even narrower temperature difference, likely no more than three degrees delta with the average somewhere around 55 degrees. So, not even a “warm” spot actually, but a “slightly less cold” spot. It could be a gap in the wall insulation or an electrical cable near the drywall under a small load. We don’t know, we may never know, and nobody should be concerned. My reaction was to you calling it a “hot” spot and trying to interpret a three degree delta as something significant. I get that that you are just curious, I would be as well, but for only about the two seconds it would take to interpret the (cold, narrow) temperature range and decide it was not important.
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Here is an example that I came across today of the heat signature from a refrigerant line contained inside an exterior wall.
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Could be reflected heat. IE like reflected heat from a neighbors window that can melt siding.
Even reflected light from a bathroom or bedroom mirror or a shiny reflective surface. I chased reflected light to a bathroom tiles or first floor windows while I was inspecting the second floor hallway.
Was it a Heat Pump running in the heat mode?
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Yes it was in heat mode. I don’t believe it would be possible to see the heat signature from the liquid line in cool mode.
It is most common to see this when the heat pump is running in the heating mode, as the section line is hot.
Consider the temperature rise when analyzing this. This shows that the pipe is against the sheet rock wall (potentially), but because the pipe is insulated with armor flex heat transfer rate should not be significant. To test for missing insulation on the section line, switchover to cooling mode in the hotspot will immediately become cool.
As for finding this in the cooling mode, the liquid line can get hot if the condenser coil is dirty and does not give up its heat at the condensing coil.
Hmm. If the AC is running properly, the liquid line (heading towards the evaporator) in cool mode is likely to be around 10 degrees warmer than ambient. If the line is uninsulated and next to the drywall, it would probably show up in a thermal.
The liquid refrigerant exiting the compressor should be around 30 degrees above ambient. The top of the compressor is typically the hottest thing inside the condenser. The condenser coils (if clean and efficient) will cool the liquid down about 20 degrees (30 degrees - 20 = 10 degrees)
As David indicated, if the AC condenser coils are dirty / not working well, the liquid line could be 15, 20 degrees or more above ambient.
That is true. I could see how the liquid line heat signature could show as well if the conditions were right.